The three-day window runs through Sept 5. Crews are prioritising the Batang Ai, Murum and Bakun hydropower dams, then 13 water catchments across Samarahan, Sri Aman, Betong, Kapit and Limbang. Seeding can only happen when suitable moisture-rich clouds form between about 5,000 and 7,000 feet.

That condition remains the limit. Earlier forecasts had found clouds unsuitable and winds pushing them out to sea; even after take-off, not every target is guaranteed to be seeded or receive rain. Officials said reservoir levels were lower than usual but still under control.

The mission is meant to replenish dams and catchments, with cleaner air as a possible benefit rather than a promised result. Its effect will have to be measured through subsequent rainfall, reservoir levels and API readings — the flight itself does not guarantee immediate rain for Kuching.